Arguably Mildenhall could also close and its roles and responsibilities could be moved to Fairford.
Assuming that the 493rd's F-15Cs do go, could the two F-15E squadrons be accommodated at Mildenhall, thereby allowing the continued use of Lakenheath's existing domestic site? Fairford could be brought into more regular use, hosting the current ferry/transit/staging flights that currently use Mildenhall.
Just a thought, no idea what the feasibility is.